Oatmeal is hocus pocus “nutrition”...
https://www.wheatbellyblog.com/2019/09/the-truth-about-oats-and-oatmeal/
I am not a big believer in the food pyramid myself. As anything, everything in moderation. Personally found that when I switched to a keto style diet all my pertinent blood measurements improved. Blood sugar was never high but it dropped a lot anyway. Total cholesterol dropped, and the ratio of good to bad cholesterol improved. BP and HR both improved. And of course I lost quite a few pounds (was never obese but needed to drop some). A lot of this seems counter-intuitive to the dogma. Maybe not for everyone but at least in my case.
Yep, all these “benefits” are “associated” with eating horse feed. Correlation is not causation.
The article you linked mentioned the “sugar spike” it gives - but I defeat that by tossing a bunch of brown sugar on it....